JPWO2018066347A1 - Endoscope system and method of operating the same - Google Patents

Abstract

Abstract: An endoscope system and an operation method thereof capable of reducing visual discomfort even when normal images and special images are alternately displayed. When the observation target including the first structure is illuminated with the first mode illumination light, a first mode display image obtained by imaging the observation target is acquired. When the observation target is illuminated with the second mode illumination light, a second mode display image obtained by imaging the observation target is acquired. The first mode display image or the second mode display image or the second mode display image or the second mode display image or the second mode display image before the correction so that the difference becomes smaller with respect to the difference in the color and / or the brightness of the first structure. The mode display image is corrected to obtain a corrected image.

Description

  The present invention relates to an endoscope system that displays a natural-colored normal image and a special image with high visibility of blood vessel structure, and an operation method thereof.

  In the medical field, diagnosis using an endoscope system including a light source device, an endoscope, and a processor device is widely performed. The endoscope system irradiates illumination light emitted by the light source device to the observation target through the endoscope, and the processor device generates an image based on an image signal obtained by imaging the observation target under illumination with the illumination light. Generate an image of the observation target. By displaying this image on the monitor, the doctor can make a diagnosis while looking at the image on the monitor.

  In recent years, by using broadband light such as white light whose wavelength band extends from the blue band to the red band as illumination light, in addition to a normal image for displaying an observation target in a natural color, illumination light also has a specific wavelength. Also, a special image in which the visibility of a specific structure such as a blood vessel structure is improved by using light and by using light of multiple colors in which the light intensity of a specific color is made greater than the light intensity of other colors, It is being used for observation of the observation object. Since it is necessary to use the normal image and the special image properly according to the purpose of diagnosis, the operation of the endoscope so that the normal mode for displaying the normal image and the special mode for displaying the special mode can be appropriately switched. The unit is provided with a switch-type mode switching unit (see Patent Document 1).

JP 2008-43604 A

  As described in Patent Document 1, when the display switching between the normal image and the special image is performed by the mode switching unit, the user needs to operate the mode switching unit, which places a burden on the user. Therefore, it is conceivable to alternately display the normal image and the special image on the monitor so that both the normal image and the special image can be observed in one mode. However, when the normal image and the special image are displayed alternately in this way, the color and brightness of the normal image and the special image are different, so when switching from the normal image to the special image, the eyes may flicker, etc. May give a sense of discomfort.

  An object of the present invention is to provide an endoscope system capable of reducing visual discomfort such as flickering of eyes even when normal images and special images are alternately displayed, and an operation method thereof. Do.

  The endoscope system of the present invention observes when the light source emitting the first mode illumination light and the second mode illumination light, and the observation target including the first structure is illuminated with the first mode illumination light. Image acquisition for acquiring the first mode display image obtained by imaging the object and the second mode display image obtained by imaging the observation object when the observation object is illuminated with the second mode illumination light And an image correction unit for correcting the first mode display image or the second mode display image to obtain a corrected image, the first structure in the first mode display image or the second mode display image before correction And an image correction unit that corrects the difference in color and / or brightness so as to reduce the difference.

  The image correction unit is a color and / or brightness acquisition unit for acquiring the color and / or brightness of the first structure from the display image for the first mode, and the color of the first structure in the display image for the second mode before correction. And / or the color and / or the brightness of the second mode display image so that the difference is small with respect to the difference between the color and / or the brightness of the first structure acquired by the color and / or the brightness and / or the brightness acquiring unit It is preferable to have a color and / or brightness adjustment unit that performs correction for adjusting the brightness.

  The image correction unit is a color and / or brightness storage unit for storing in advance the color and / or brightness of the first structure, and the color and / or brightness and color of the first structure in the second mode display image before correction. And / or a correction for adjusting the color and / or the brightness of the second mode display image so that the difference is small with respect to the difference between the color and / or the brightness of the first structure stored in the and / or the brightness storage unit It is preferable to have a color and / or brightness adjustment unit that

  The observation target includes the second structure, and the image correction unit is configured to change the color and / or the brightness of the first structure and the second structure in the display image for the first mode or the display image for the second mode before correction. On the other hand, it is preferable to correct the first mode display image or the second mode display image so as to reduce the difference. The image correction unit extracts the second structure from the second mode display image to generate the second mode display image after the second structure extraction, or removes the second structure from the second mode display image. Thus, the second structure extraction unit generates the first structure extracted second mode display image from which the first structure is extracted, and the second mode display image with reference to the first structure extracted second mode display image. The correction for adjusting the color and / or the brightness of the first structure in the display image is performed, or the second structure in the second mode display image is referred to with reference to the second mode display image after the second structure extraction. It is preferable to have a color and / or brightness adjustment unit that performs correction to adjust color and / or brightness. Preferably, the first structure is a mucosal structure and the second structure is a vascular structure.

  A display unit for displaying an uncorrected image not corrected by the image correction unit among the first mode display image or the second mode display image, and a corrected image, and a display control unit for controlling the display unit Is preferred. The display control unit preferably controls the display unit such that the uncorrected image and the corrected image are alternately displayed. The display control unit preferably includes a display pattern setting unit configured to set a display pattern including display times of the uncorrected image and the corrected image in the display unit. It is preferable to have a composite image generation unit that generates a composite image obtained by combining the uncorrected image and the corrected image, and the display unit displays the uncorrected image, the composite image, and the corrected image.

  The first mode illumination light emits light of one or more colors under the first mode emission condition, and the second mode illumination light emits one or more colors of light for the first mode emission It is preferable that the light be emitted under the second mode light emission conditions different from the conditions.

  When the illumination light for the first mode is light that emits light of a plurality of colors simultaneously, the display image for the first mode is an image obtained by imaging an observation target in which the lights of a plurality of colors are simultaneously illuminated. If the illumination light for the first mode is light emitting light of a plurality of colors sequentially, the display image for the first mode is obtained by sequentially imaging the observation target in which the light of each color is sequentially illuminated. Image is preferable.

  When the illumination light for the second mode is light that emits light of a plurality of colors simultaneously, the display image for the second mode is an image obtained by imaging an observation target in which the lights of a plurality of colors are simultaneously illuminated. If the illumination light for the second mode is light that sequentially emits light of a plurality of colors, the display image for the second mode is obtained by sequentially imaging the observation target in which the light of each color is sequentially illuminated. Image is preferable.

  The endoscope system of the present invention is an observation target when the observation target including the light source emitting the illumination light for the first mode and the illumination light for the second mode and the mucous membrane structure is illuminated with the illumination light for the first mode. An image acquisition unit configured to acquire a first mode display image obtained by imaging the image and a second mode display image obtained by imaging the observation object when the observation object is illuminated with the second mode illumination light And an image correction unit that corrects the first mode display image or the second mode display image to obtain a corrected image, and has a first structure in the first mode display image or the second mode display image before correction. The image correction unit corrects the difference between the color and / or the brightness so that the difference is reduced, and the display control unit controls the display unit. To obtain the color and / or brightness of the According to the difference between the color and / or brightness of the first structure and / or the color and / or the color and / or brightness of the first structure obtained by the brightness acquiring part in the display image for the second mode before correction And a color and / or brightness adjustment unit that performs correction to adjust the color and / or brightness of the second mode display image so that the difference is reduced, and the display control unit is for the first mode. Control is performed so that the display image and the display image for the second mode after brightness adjustment by the brightness adjustment unit are alternately displayed on the display unit.

  In the method of operating the endoscope system according to the present invention, the light source emits the first mode illumination light and the second mode illumination light, and the image acquisition unit emits the first mode illumination light. A first mode display image obtained by imaging the observation target including the first structure, and a second mode display image obtained by imaging the observation target when the second mode illumination light is emitted; And the image correction unit corrects the first mode display image or the second mode display image to obtain a corrected image, and the first mode display image before the correction or the second And correcting the difference in color and / or brightness of the first structure in the mode display image so as to reduce the difference.

  According to the present invention, even when a normal image and a special image are alternately displayed, visual discomfort such as flickering of eyes can be reduced.

It is an external view of an endoscope system. It is a block diagram which shows the function of the endoscope system of 1st Embodiment. It is a graph which shows the spectrum of purple light V, blue light B, blue light Bx, green light G, and red light R. It is a table | surface which shows the pattern of the illumination light light-emitted in the normal mode of the 1st embodiment, a special mode, and mixed mode. It is a block diagram which shows the function of an image correction part and a display control part. It is explanatory drawing which shows the production | generation method of the special image in which the blood vessel extraction was completed, and the special image in which the mucous membrane extraction was completed. It is an image figure of the monitor which displays a normal image and a correction special image by turns. It is an explanatory view showing a flow of a picture display on a monitor in case display time Tc of a usual picture is longer than display time Ts of amendment special picture. It is explanatory drawing which shows the flow of a display of the image in the monitor in case the display time Ts of a correction | amendment special image is longer than the display time Tc of a normal image. It is a flowchart which shows the flow of mixed mode. It is a block which shows the function of an image correction part provided with a color and / or brightness storage part, and the function of a display control part. It is a block which shows the function of an image correction part provided with a synthetic | combination image generation part, and the function of a display control part. It is explanatory drawing which shows the flow of a display of the image in the monitor in, when displaying a normal image, a synthetic | combination image, and a correction | amendment special image. It is a table | surface which shows the pattern of the illumination light light-emitted in the normal mode of the 2nd embodiment, a special mode, and mixed mode. It is a block diagram which shows the function of the endoscope system of 3rd Embodiment. It is a graph which shows the spectrum of white light for the normal mode. It is a graph which shows the spectrum of white light for special modes. It is a block diagram which shows the function of the endoscope system of 4th Embodiment. It is a top view of a rotation filter. It is a table | surface which shows the pattern of the illumination light light-emitted in the normal mode of the 4th embodiment, a special mode, and mixed mode. It is the schematic of the capsule endoscope of 5th Embodiment.

First Embodiment
As shown in FIG. 1, the endoscope system 10 includes an endoscope 12, a light source device 14, a processor device 16, a monitor 18 (display unit), and a console 19. The endoscope 12 is optically connected to the light source device 14 and electrically connected to the processor device 16. The endoscope 12 has an insertion portion 12a to be inserted into a subject, an operation portion 12b provided at a proximal end portion of the insertion portion 12a, and a curved portion 12c and a distal end portion 12d provided on the distal end side of the insertion portion 12a. doing. By operating the angle knob 13a of the operation unit 12b, the bending portion 12c performs a bending operation. By this bending operation, the tip 12d is directed in a desired direction.

  In addition to the angle knob 13a, a still image acquisition unit 13b used for a still image acquisition operation, a mode switching unit 13c used for an observation mode switching operation, and a zoom operation unit used for a zoom magnification change operation in the operation unit 12b. 13 d is provided. The still image acquisition unit 13 b can perform a freeze operation for displaying a still image to be observed on the monitor 18 and a release operation for storing the still image in a storage.

  The endoscope system 10 has, as an observation mode, a normal mode, a special mode, and a mixed mode in which both the normal mode and the special mode are performed. When the observation mode is the normal mode, the light source device 14 emits the illumination light for the normal mode under the light emission condition for the normal mode (corresponding to the “light emission condition for the first mode” of the present invention) A normal image is displayed on the monitor 18 based on an image signal obtained by imaging an observation target being illuminated with illumination light.

  When the observation mode is the special mode, the light source device 14 has the special mode light emission condition different from the normal mode light emission condition (corresponding to the “second mode light emission condition” in the present invention). The special image is displayed on the monitor 18 based on the image signal obtained by imaging the observation target under illumination with the special mode illumination light. When the observation mode is the mixed mode, the light source device 14 alternately emits the normal mode illumination light and the special mode illumination light, and alternately displays the normal image and the special image on the monitor 18.

  The processor unit 16 is electrically connected to the monitor 18 and the console 19. The monitor 18 outputs and displays an image to be observed, information attached to the image, and the like. The console 19 functions as a user interface that receives input operations such as specification of a region of interest (ROI) and function settings. The hardware-like structure of each part in the processor device is various processors as shown below. For various processors, the circuit configuration has been changed after manufacturing CPU (Central Processing Unit), which is a general-purpose processor that executes software (program) and functions as various processing units, and FPGA (Field Programmable Gate Array) Logic circuit (Programmable Logic Device (PLD)) which is a possible processor, a dedicated electric circuit which is a processor having a circuit configuration specially designed to execute specific processing such as ASIC (Application Specific Integrated Circuit), etc. included. The same applies to each part inside the endoscope 12 and the light source device 14.

  As shown in FIG. 2, the light source device 14 includes a light source 20 that emits illumination light used for illumination of an observation target, and a light source control unit 22 that controls the light source 20. The light source 20 is a semiconductor light source such as a plurality of colors of LEDs (Light Emitting Diodes). The light source control unit 22 controls the light emission amount of the illumination light by turning on / off the LED or the like, and adjusting the drive current or the drive voltage of the LED or the like. The light source control unit 22 also controls the wavelength band of the illumination light by changing the optical filter or the like.

  In the first embodiment, the light source 20 includes a V-LED (Violet Light Emitting Diode) 20a, a B-LED (Blue Light Emitting Diode) 20b, a G-LED (Green Light Emitting Diode) 20c, and an R-LED (Red Light). It has four color LEDs of Emitting Diode) 20 d and a wavelength cut filter 23. As shown in FIG. 3, the V-LED 20 a emits violet light V in a wavelength band of 380 nm to 420 nm.

  The B-LED 20b emits blue light B in a wavelength band of 420 nm to 500 nm. Of the blue light B emitted from the B-LED 23 b, the wavelength cut filter 23 cuts off at least the wavelength side longer than 450 nm of the peak wavelength. Thereby, the blue light Bx after passing through the wavelength cut filter 23 is in the wavelength range of 420 to 460 nm. As described above, the reason why light in the wavelength range longer than 460 nm is cut is a factor that reduces the blood vessel contrast of the blood vessel to be observed. It is because there is. The wavelength cut filter 23 may reduce the light in the wavelength range longer than 460 nm instead of cutting the light in the wavelength range longer than 460 nm.

  The G-LED 20c emits green light G having a wavelength band ranging from 480 nm to 600 nm. The R-LED 20d emits red light R in a wavelength band of 600 nm to 650 nm. The light emitted from each of the LEDs 20a to 20d may have the same or different central wavelength and peak wavelength.

  The light source control unit 22 adjusts the light emission timing, the light emission period, the light amount, and the spectral spectrum of the illumination light by independently controlling lighting and extinguishing of each of the LEDs 20 a to 20 d and the light emitting amount at lighting. The control of lighting and extinguishing in the light source control unit 22 is different for each observation mode.

  As shown in FIG. 4, in the case of the normal mode, the light source control unit 22 turns on all of the V-LED 20 a, the B-LED 20 b, the G-LED 20 c, and the R-LED 20 d. At that time, the light amount ratio Lc among the purple light V, the blue light B, the green light G, and the red light R is any light emission amount of the blue light Bx, which is either purple light V, green light G or red light R It is set to be larger than the amount. Thus, in the normal mode, the light source device 14 emits normal mode illumination light including violet light V, blue light Bx, green light G, and red light R. The illumination light for normal mode is almost white because it has a certain intensity or more from the blue band to the red band. The light emission condition for the normal mode corresponds to “simultaneous emission of purple light V, blue light Bx, green light G, and red light R at the light amount ratio Lc”.

  Also in the case of the special mode, the light source control unit 22 turns on all of the V-LED 20a, the B-LED 20b, the G-LED 20c, and the R-LED 20d. At that time, the light amount ratio Ls among the purple light V, the blue light B, the green light G, and the red light R is any light emission amount of the purple light V, that is, any light of blue light Bx, green light G and red light R The green light G and the red light R are set to be smaller than the violet light V and the blue light Bx so as to be larger than the amount. Thereby, in the special mode, illumination light for special mode including the violet light V, the blue light Bx, the green light G, and the red light R is emitted from the light source device 14. The special mode light emission condition corresponds to "simultaneous emission of purple light V, blue light Bx, green light G, and red light R at the light amount ratio Ls".

  In the mixed mode, the light source control unit 22 turns on all the V-LEDs 20a, B-LEDs 20b, G-LEDs 20c, and R-LEDs 20d, and changes the light amount ratio from "Lc" to "Ls" in frame units. Or switch from "Ls" to "Lc". That is, in the light emitted from the light source device 14, the normal mode illumination light and the special mode illumination light are alternately switched.

  As shown in FIG. 2, the illumination light emitted from the light source 20 is incident on the light guide 24 inserted into the insertion portion 12 a via an optical path coupling portion (not shown) formed by a mirror, a lens or the like. The light guide 24 is incorporated in the endoscope 12 and the universal cord, and propagates the illumination light to the distal end 12 d of the endoscope 12. The universal cord is a cord that connects the endoscope 12 to the light source device 14 and the processor device 16. As the light guide 24, a multimode fiber can be used. As an example, for the light guide 24, a small diameter fiber cable with a core diameter of 105 μm, a cladding diameter of 125 μm, and a diameter of φ0.3 mm to φ0.5 mm including a protective layer to be an outer cover can be used.

  An illumination optical system 30 a and an imaging optical system 30 b are provided at the distal end 12 d of the endoscope 12. The illumination optical system 30 a has an illumination lens 32. The observation target is illuminated with illumination light transmitted through the light guide 24 through the illumination lens 32. The imaging optical system 30 b has an objective lens 34, a zoom lens 36, and an imaging sensor 38. Various types of light such as reflected light, scattered light, and fluorescent light from the observation target enter the imaging sensor 38 through the objective lens 34 and the zoom lens 36. Thereby, the image of the observation object is formed on the imaging sensor 38. The zoom lens 36 freely moves between the tele end and the wide end by operating the zoom operation unit 13 d, and magnifies or reduces the observation target formed on the imaging sensor 38.

  The imaging sensor 38 is a color imaging sensor for imaging the observation target irradiated with the illumination light. Each pixel of the imaging sensor 38 is provided with one of an R (red) color filter, a G (green) color filter, and a B (blue) color filter. The imaging sensor 38 receives light from purple to blue at the B pixel provided with the B color filter, receives green light at the G pixel provided with the G color filter, and is provided with the R color filter. The red light is received by the R pixel. Then, an image signal of each color of RGB is output from the pixel of each color. The imaging sensor 38 transmits the output image signal to the CDS / AGC circuit 40.

  In the normal mode, the imaging sensor 38 outputs a Bc image signal from the B pixel and outputs a Gc image signal from the G pixel by imaging the observation target illuminated with the illumination light for the normal mode, and from the R pixel Output Rc image signal. Further, in the special mode, the imaging sensor 38 outputs a Bs image signal from the B pixel and outputs a Gs image signal from the G pixel by imaging the observation target illuminated with the illumination light for special mode. The Rs image signal is output from the pixel.

  During illumination of the normal mode illumination light in the mixed mode, the imaging sensor 38 outputs a Bc image signal, a Gc image signal, and an Rc image signal by imaging the observation target illuminated by the normal mode illumination light. Further, during illumination of the special mode illumination light in the mixed mode, the imaging sensor 38 outputs a Bs image signal, a Gs image signal, and an Rs image signal by imaging the observation target illuminated with the special mode illumination light. Do.

  As the imaging sensor 38, a charge coupled device (CCD) imaging sensor, a complementary metal-oxide semiconductor (CMOS) imaging sensor, or the like can be used. Also, a complementary color imaging sensor provided with complementary color filters of C (cyan), M (magenta), Y (yellow) and G (green) may be used instead of the imaging sensor 38 provided with color filters of RGB primary colors. good. When a complementary color imaging sensor is used, an image signal of four colors CMYG is output. For this reason, by converting the CMYG four-color image signal into the RGB three-color image signal by complementary color-primary color conversion, it is possible to obtain an image signal of each RGB color similar to that of the imaging sensor 38. Also, instead of the imaging sensor 38, a monochrome sensor not provided with a color filter may be used.

  The CDS / AGC circuit 40 performs correlated double sampling (CDS) and automatic gain control (AGC) on the analog image signal received from the imaging sensor 38. An A / D (Analog to Digital) conversion circuit 42 converts an analog image signal passed through the CDS / AGC circuit 40 into a digital image signal. The A / D conversion circuit 42 inputs the digital image signal after A / D conversion to the processor unit 16.

  The processor unit 16 includes an image signal acquisition unit 50, a DSP (Digital Signal Processor) 52, a noise reduction unit 54, an image processing unit 58, and a display control unit 60.

  The image signal acquisition unit 50 (corresponding to the “image acquisition unit” of the present invention) acquires a digital image signal corresponding to the observation mode from the endoscope 12. In the case of the normal mode, a Bc image signal, a Gc image signal, and an Rc image signal are acquired as a normal image (corresponding to the “display image for the first mode” of the present invention). In the case of the special mode, a Bs image signal, a Gs image signal, and an Rs image signal are acquired as a special image (corresponding to the “display image for the second mode” of the present invention). In the case of the mixed mode, the Bc image signal, the Gc image signal, and the Rc image signal are acquired as the normal image, and the Bs image signal, the Gs image signal, and the Rs image signal are acquired as the special image.

  The DSP 52 performs various signal processing such as defect correction processing, offset processing, gain correction processing, linear matrix processing, gamma conversion processing, and demosaicing processing on the image signal acquired by the image signal acquisition unit 50. The defect correction process corrects the signal of the defective pixel of the imaging sensor 38. In the offset process, the dark current component is removed from the image signal subjected to the defect correction process, and an accurate zero level is set. In the gain correction processing, the signal level is adjusted by multiplying the offset-processed image signal by a specific gain.

  Linear matrix processing enhances the color reproducibility of the image signal subjected to gain correction processing. In gamma conversion processing, the brightness and saturation of the image signal subjected to linear matrix processing are adjusted. The image signal subjected to the gamma conversion process is subjected to a demosaicing process (also referred to as isotropization process or synchronization process) to generate a signal of a color lacking in each pixel by interpolation. By this demosaicing process, all pixels have signals of RGB colors. The noise reduction unit 54 reduces noise by performing noise reduction processing using, for example, a moving average method or a median filter method on the image signal that has been subjected to the demosaicing processing or the like by the DSP 52.

  The image processing unit 58 includes a normal image generation unit, a special image processing unit 64, and an image correction unit 66. The normal image processing unit 62 operates when the normal mode or the mixed mode is set, and performs color conversion processing, color enhancement processing, and structure enhancement processing on the received normal image. In color conversion processing, color conversion processing is performed on an RGB image signal by 3 × 3 matrix processing, tone conversion processing, three-dimensional LUT (Look Up Table) processing, or the like.

  The color emphasizing process is performed on the color converted image signal. The structure emphasizing process is a process of emphasizing the structure of the observation target, and is performed on the image signal after the color emphasizing process. As described above, a normal image subjected to various image processing and the like up to the structure emphasizing process is obtained based on the illumination light for normal mode in which violet light V, blue light Bx, green light G and red light R are emitted in a well-balanced manner. The image is a natural color image because it is a The normal image is input to the display control unit 60 as it is when the normal mode is set, and is input to the display control unit 60 and the image correction unit 66 when the mixed mode is set.

  The special image processing unit 64 operates when the special mode or the mixed mode is set. The special image processing unit 64 performs color conversion processing, color enhancement processing, and structure enhancement processing on the received special image. The processing contents of the color conversion process, the color emphasis process, and the structure emphasis process are the same as in the normal image processing unit 62. The special image is obtained based on the special mode illumination light in which the purple light V having a high absorption coefficient of the blood vessel hemoglobin has a larger emission amount than the blue light Bx, green light G and red light R of other colors. Since the image is an isolated image, the resolution of the vascular structure is higher than other structures. The special image is directly input to the display control unit 60 when the special mode is set, and is input to the image correction unit 66 when the mixed mode is set.

  The image correction unit 66 operates when the mixing mode is set, and corrects the special image. In this image correction unit 66, the difference between the color and / or brightness of the blood vessel structure or mucous membrane structure in the special image before correction and the color and / or brightness of the mucous membrane structure in the normal image is reduced. Correct the special image. Details of the image correction unit 66 will be described later. The corrected special image obtained by correcting the special image by the image correction unit 66 is transmitted to the display control unit 60. Note that the image correction unit 66 may perform correction so that the difference between both the color and the brightness is reduced, and even if the difference between one of the color and the brightness is reduced, the correction may be performed. Good.

  The display control unit 60 performs display control for displaying an image from the image processing unit 58 on the monitor 18. When the normal mode is set, the display control unit 60 performs control to display a normal image on the monitor 18. When the special mode is set, the display control unit 60 performs control to display the special image on the monitor 18. When the mixed mode is set, the normal image and the corrected special image are displayed according to the set display pattern. Details of display control in this mixed mode will be described later.

  As shown in FIG. 5, the image correction unit 66 includes a structure extraction unit 70, a color and / or brightness acquisition unit 72, and a color and / or brightness adjustment unit 74. The structure extraction unit 70 generates a blood vessel-extracted special image by extracting a blood vessel structure from the special image, as shown in FIG. As a method of extracting the blood vessel structure, for example, in addition to a method of binarizing the blood vessel and the other part using a predetermined threshold value, the ratio or difference of the Bs image signal of the special image and the Gs image signal is obtained. Can be considered a method of extracting blood vessels. The structure extraction unit 70 similarly generates a normal image after blood vessel extraction by extracting the blood vessel structure from the normal image.

  If it is difficult to extract the blood vessel structure from the normal image, the structure on the normal image at the same position as the blood vessel structure extracted from the special image may be extracted as the blood vessel structure. However, if all the structures at the same position as the blood vessel structure of the special image are regarded as the blood vessel structure, there is a possibility that a structure which can not be seen in the normal image may be extracted as the blood vessel structure. Therefore, among the blood vessel structures of the special image, it is preferable to extract a structure having a low resolution that can be visually recognized even in the normal image, regarding the structure at the same position on the normal image as the blood vessel structure.

  The structure extraction unit 70 generates a special image after blood vessel removal from which the blood vessel structure has been removed from the special image by performing difference processing between the special image and the special image after blood vessel extraction. The blood vessel removed special image is a mucous membrane-extracted image in which the blood vessel structure is removed and substantially only the mucosal structure is extracted. As described above, the difference image between the special image and the special image after blood vessel extraction is used to generate the special image after the mucous membrane extraction, because the mucous membrane structure does not have much difference in pixel value with other parts. It is because it is difficult to extract only the mucous membrane structure. Further, the structure extraction unit 70 similarly performs a subtraction process on the normal image and the normal image after blood vessel extraction to remove the blood vessel structure from the normal image. Generate an image).

  The color and / or brightness acquisition unit 72 acquires the color and / or brightness of the blood vessel structure from the blood vessel-extracted normal image. Further, the color and / or brightness acquisition unit 72 acquires the color and / or brightness of the mucous membrane structure from the mucous membrane-extracted normal image. The color of the acquired blood vessel structure or mucosal structure is preferably averaged, and the lightness of the acquired blood vessel structure or mucosal structure is also preferably averaged. Here, as a method of acquiring color or brightness, for example, a method of performing processing of separating color and brightness on a blood vessel-extracted normal image can be considered. When a normal image after blood vessel extraction is converted into a luminance signal Y and color difference signals Cr and Cb, the luminance signal Y corresponds to the brightness of the blood vessel structure, and the color difference signals Cr and Cb correspond to the color of the blood vessel structure. become. In addition, it is preferable that the color and / or brightness acquisition unit 72 acquire at least one of the color and the brightness of the blood vessel structure.

  The color and / or brightness adjustment unit 74 refers to the position of the blood vessel structure in the blood vessel extracted special image, and acquires the color and / or brightness and color and / or brightness acquisition unit of the blood vessel structure in the special image before correction A correction is made to adjust the color and / or brightness of the special image so that the difference between the color and / or brightness of the blood vessel structure acquired at 72 is reduced. Further, the color and / or brightness adjustment unit 74 refers to the position of the mucous membrane structure in the mucous membrane-extracted special image, and the color and / or brightness of the mucous membrane structure in the special image before correction, and the color and / or brightness With respect to the difference between the color and / or brightness of the mucous membrane structure obtained by the depth obtaining unit 72, correction is performed to adjust the color and / or brightness of the special image so that the difference is reduced. This results in a corrected special image in which the color and / or brightness of the vascular or mucosal structure is close to the color and / or brightness of the normal image.

  Note that “the difference in color and / or brightness is reduced” means that the color and / or brightness of the blood vessel structure or mucous membrane structure in the special image is acquired by the color and / or brightness acquisition unit 72 or Besides matching with the average value of the color and / or brightness of the mucous membrane structure, the color and / or brightness of the blood vessel structure or mucous membrane structure in the special image is acquired by the color and / or brightness acquisition unit 72 Or it means within the fixed range including the average value of the color and / or brightness of a mucous membrane structure.

  The display control unit 60, as shown in FIG. 7, displays the normal image Pc (corresponding to the "uncorrected image" of the present invention) and the corrected special image Ps (corresponding to the "corrected image" of the present invention) on the monitor 18. Control is performed to issue a display instruction to the monitor 18 so as to alternately display. Since the normal image Pc and the correction special image Ps are alternately displayed on the monitor 18, it is possible to observe both the normal image Pc and the correction special image Ps without operating the mode switching unit 13c. In the correction special image Ps, a blood vessel structure Vs which can not be observed in the normal image Pc can also be observed, and such a blood vessel structure Vs contributes to an effective diagnosis. Also, even if the normal image Pc and the corrected special image Ps are displayed alternately, the color and / or the brightness of the mucous membrane structure Mc and the blood vessel structure Vs that occupy most of the corrected special image Ps and the color and / or Or, since the difference with the brightness is small, there is no risk of visual discomfort such as flickering of eyes.

  The display control unit 60 also has a display pattern setting unit 76 that sets the display pattern of the normal image displayed on the monitor 18 and the correction special image. The setting of the display pattern is performed by operating the display pattern setting unit 76 by an input device such as the console 19. The display pattern setting unit 76 sets a display time Tc of a normal image and a display time Tc of a corrected special image as display patterns. The display control unit 60 instructs the monitor 18 to display a normal image and a corrected special image according to the display time set by the display pattern setting unit 76.

  For example, when the display time Tc of the normal image is set longer than the display time Tc of the corrected special image, one frame of the normal image is displayed after several frames of the normal image are displayed as shown in FIG. It becomes a display pattern in which a correction special image is displayed. This display pattern is suitable, as in screening, to observe the whole of the observation target and not to overlook a lesion. On the other hand, if the display time Tc of the corrected special image is set longer than the display time Tc of the normal image, as shown in FIG. 9, after several frames of the corrected special image are displayed, It becomes a display pattern in which a normal image for one frame is displayed. This display pattern is suitable for observing the nature of a lesion in detail, such as at the time of detailed observation.

  Next, a series of flows of the mixing mode will be described along the flowchart of FIG. The mode switching unit 13c is operated to switch to the mixing mode. Thus, the normal mode illumination light and the special mode illumination light are alternately emitted. That is, violet light V, blue light Bx, green light G, and red light R are simultaneously emitted as the illumination light for the normal mode at a light amount ratio Lc, and then violet light V, blue light Bx as the illumination light for special mode , Green light G and red light R are simultaneously emitted at a light amount ratio Ls.

  Then, the imaging sensor 38 picks up an image of an observation target illuminated with purple light V, blue light Bx, green light G, and red light R at the light amount ratio Lc, thereby comprising a Bc image signal, a Gc image signal, and an Rc image signal. A normal image is obtained. In addition, the imaging sensor 38 picks up an observation target illuminated with purple light V, blue light Bx, green light G, and red light R at a light amount ratio Ls, thereby comprising a Bc image signal, a Gc image signal, and an Rc image signal. A special image is obtained.

  When the normal image and the special image are generated, the normal image and the special image are input to the image correction unit 66. The structure extraction unit 70 extracts a blood vessel structure from the special image to generate a blood vessel-extracted special image, and removes a blood vessel structure from the special image to generate a mucous membrane-extracted special image. Similarly, the blood vessel structure is extracted from the normal image to generate a blood vessel-extracted normal image, and the blood vessel structure is removed from the normal image to generate a mucosal-extracted normal image from which the mucosal structure is extracted.

  Next, the color and / or brightness acquisition unit 72 acquires the average value of the color and / or brightness of the blood vessel structure from the blood vessel-extracted normal image, and the mucous membrane structure color and / Or get the average value of brightness. Then, the color and / or brightness adjustment unit 74 refers to the position of the blood vessel structure in the blood vessel extracted special image, and the color and / or brightness and color and / or brightness of the blood vessel structure of the special image before correction With respect to the difference between the color and / or the brightness of the blood vessel structure acquired by the acquisition unit 72, correction is performed to adjust the color and / or the brightness of the special image so that the difference is reduced. Further, with reference to the position of the mucous membrane structure in the mucous membrane-extracted special image, the color and / or brightness of the mucous membrane structure of the special image before correction and the color of the mucous membrane structure obtained by the color and / or brightness acquisition unit 72 In order to reduce the difference between the image and the brightness, the color and / or the brightness of the special image is adjusted. As described above, the correction special image is obtained by performing the correction for adjusting the color and / or the brightness of the blood vessel structure or the mucous membrane structure.

  Next, the display control unit 60 controls to alternately display the normal image and the correction special image on the monitor 18 according to the specific display pattern. At the time of display control by the display control unit 60, the display pattern setting unit 76 adjusts the display time Tc of the normal image and the display time Ts of the corrected special image as the specific display pattern.

  In the above embodiment, the color and / or brightness of the blood vessel structure or mucous membrane structure is obtained from the normal image, and the special image is corrected so as to be the color and / or brightness of the obtained blood vessel structure or mucous membrane structure. Alternatively, the color and / or brightness of the average vascular or mucosal structure may be stored in advance, and the color or brightness of the previously stored vascular or mucosal structure may be obtained. The special image may be corrected. In this case, as shown in FIG. 11, in the image correction unit 66, a color and / or brightness storage unit 80 is provided instead of the color and / or brightness acquisition unit 72. By providing this color and / or brightness storage unit 80, the structure extraction unit 70 does not need to acquire a normal image after blood vessel extraction and a normal image after mucosal extraction.

  In the color and / or brightness storage unit 80, the average value of the color and / or brightness of the blood vessel structure or the mucosal structure is stored. The average value of the color and / or brightness of the blood vessel structure or mucous membrane structure stored in the color and / or brightness storage unit 80 images, for example, a predetermined site (esophagus, stomach, large intestine) in advance in the normal mode. It is preferable to calculate from the normal image obtained by In addition, the average value of the color and / or brightness of the blood vessel structure or the mucous membrane structure is stored for each region such as the stomach and large intestine, and the blood and / or brightness adjusting unit 74 is used depending on the region to be observed. The color and / or brightness average value of the structure or mucosal structure may be switched.

  In the above embodiment, the normal image and the corrected special image are alternately displayed, but in addition to the normal image and the corrected special image, the normal image and the corrected special image are synthesized between the normal image and the corrected special image. The composite image may be displayed. In this case, as shown in FIG. 12, the image processing unit 58 is provided with a composite image generation unit 84 for combining the normal image and the corrected special image. The composite image generation unit 84 generates a composite image by adding a specific weight to the normal image and the correction special image and adding them.

  The composite image is an image in which the color and / or the brightness is close to that of the normal image or the correction special image by setting the specific weighting coefficient to an approximately intermediate value. The generated composite image is displayed between the normal image and the corrected special image as shown in FIG. As described above, when a composite image is inserted and displayed between the normal image and the correction special image, a change in color and / or brightness as compared to the case where the normal image and the correction special image are alternately displayed. Becomes milder, which can further reduce visual discomfort such as flickering of eyes.

  In the above embodiment, the special image is corrected by the image correction unit 66. Alternatively, the normal image may be corrected. In this case, the difference between the color and / or brightness of the blood vessel structure or mucosal structure in the normal image before correction and the color and / or brightness of the blood vessel structure or mucosal structure of the special image is reduced. In addition, correction may be performed to adjust the color and / or brightness of the normal image. When a normal image is corrected, a corrected normal image (corresponding to the “corrected image” of the present invention) and a special image (corresponding to the “uncorrected image” of the present invention) are alternately displayed. Become.

  In addition, although the color and / or brightness adjustment unit 74 performs correction to adjust the color and / or brightness for both the blood vessel structure and the mucous membrane structure, at least one color of the blood vessel structure or the mucous membrane structure and The brightness may be adjusted. In addition to adjusting both the color and the brightness, at least one of the color and the brightness may be adjusted.

Second Embodiment
In the first embodiment, all of purple light V, blue light Bx, green light G and red light R are simultaneously emitted as the special mode illumination light in the special mode, but in the second embodiment, as shown in FIG. As shown in 14, in the special mode, violet light V and blue light Bx are alternately emitted as the special mode illumination light. Further, in the mixed mode, purple light V, blue light Bx, green light G, and red light R are simultaneously emitted as the illumination light for the normal mode at the light amount ratio Lc, and then purple light as the illumination light for the special mode. V and blue light Bx are emitted alternately.

  In the second embodiment, the light emission condition for the special mode corresponds to “emitting alternately purple light V and blue light Bx”. Further, in the second embodiment, while light of a plurality of colors is emitted simultaneously for the illumination light for the normal mode, light of a plurality of colors is emitted like illumination of purple light V and blue light Bx for the illumination light for special mode. Alternatively, the normal mode illumination light may emit light of a plurality of colors sequentially, and the special mode illumination light may emit light of a plurality of colors simultaneously.

  In the second embodiment, when the special mode illumination light is emitted in the special mode or the mixed mode, the image signal output from the imaging sensor 38 is different from that of the first embodiment. When purple light V and blue light Bx are alternately emitted as illumination light for special mode, when the purple light V is emitted, the image pickup object captures an image of the observation target and outputs a B1 image signal from the B pixel. , G pixels output the G1 image signal, R pixels output the R1 image signal. Further, when the blue light Bx is emitted, the observation target is imaged by the imaging sensor 38, the B2 image signal is output from the B pixel, the G2 image signal is output from the G pixel, and the R2 image signal is output from the R pixel Do.

  In the second embodiment, when the special mode illumination light is emitted in the special mode or the mixed mode, the image signal acquired by the image signal acquisition unit 50 is different from that of the first embodiment, and the special image processing is performed. The processing content in the unit 64 is different from that of the first embodiment. Among the image signals obtained by the special mode illumination light, B1 image signal and B2 image signal are acquired as special images, and other image signals (G1 image signal, R1 image signal, G2 image signal, R2 image signal) are It is deleted etc.

  The special image processing unit 64 generates a special image based on the B1 image signal and the B2 image signal. For example, when the special image is configured by the luminance signal Y and the color difference signals Cr and Cb, it is preferable to assign the B1 image signal or the B2 image signal to the luminance signal Y. Further, it is preferable to assign an operation image of the ratio or difference between the B1 image signal and the B2 image signal multiplied by a predetermined coefficient to the color difference signals Cr and Cb. In the second embodiment, the special image processing unit 64 preferably performs color conversion processing, color enhancement processing, and structure enhancement processing on the special image.

Third Embodiment
In the third embodiment, instead of the four-color LEDs 20a to 20d shown in the first embodiment, a laser light source and a phosphor are used to illuminate the observation target. The other respects are the same as in the first embodiment.

  As shown in FIG. 15, in the endoscope system 100 of the third embodiment, a blue laser emitting blue laser light with a central wavelength of 445 ± 10 nm instead of the LEDs 20 a to 20 d of four colors in the light source 20 of the light source device 14 A light source (denoted as "445 LD", where LD represents "Laser Diode") 104 and a blue-violet laser light source (denoted as "405 LD") 106 which emits blue-violet laser light having a central wavelength of 405 ± 10 nm are provided. . The light emission from the semiconductor light emitting element of each of the light sources 104 and 106 is individually controlled by the light source control unit 108, and the light quantity ratio of the emitted light of the blue laser light source 104 and the emitted light of the blue violet laser light source 106 can be changed. It has become.

  The light source control unit 108 turns on the blue laser light source 104 in the normal mode. On the other hand, in the special mode, both the blue laser light source 104 and the blue-violet laser light source 106 are turned on, and the emission ratio of the blue laser light is controlled to be larger than the emission ratio of the blue-violet laser light doing. In the case of the mixed mode, the blue laser light source 104 and the blue-violet laser light source 106 are controlled to be alternately turned on. The laser light emitted from each of the light sources 104 and 106 described above is incident on the light guide 24.

  The half width of the blue laser light or the blue-violet laser light is preferably about ± 10 nm. In addition, as the blue laser light source 104 and the blue-violet laser light source 106, a broad area type InGaN-based laser diode can be used, and an InGaNAs-based laser diode or a GaNAs-based laser diode can also be used. In addition, a light emitter such as a light emitting diode may be used as the light source.

  In addition to the illumination lens 32, the illumination optical system 30a is provided with a phosphor 110 to which blue laser light or blue-violet laser light from the light guide 24 is incident. The phosphor 110 is excited by blue laser light to emit fluorescence. In addition, part of the blue laser light transmits without exciting the phosphor 110. The blue-violet laser light transmits without exciting the phosphor 110. The light emitted from the phosphor 110 illuminates the body to be observed through the illumination lens 32.

  Here, in the normal mode, the blue laser light is mainly incident on the phosphor 110. Therefore, as shown in FIG. 16, the blue laser light and the fluorescence emitted from the phosphor 110 by the blue laser light are usually multiplexed. The observation target is illuminated with white light for mode (corresponding to “illumination light for normal mode” of the present invention). In the special mode, since both the blue-violet laser light and the blue laser light are incident on the phosphor 110, excitation from the phosphor 110 by the blue-violet laser light, the blue laser light, and the blue laser light as shown in FIG. The observation target is illuminated with white light for a special mode (corresponding to “illumination light for a special mode” of the present invention) in which the emitted fluorescence is combined.

  In the mixed mode, since the blue-violet laser light and the blue laser light are alternately incident on the phosphor 110, the white light for the normal mode and the white light for the special mode are alternately illuminated on the observation target. In the third embodiment, the light emission condition for the normal mode corresponds to “emitting white light for the normal mode”, and the light emission condition for the special mode emits “white light for the special mode”. Correspond to the

Note that the phosphor 110 absorbs a part of blue laser light and emits a plurality of green to yellow light (for example, a YAG phosphor or a phosphor such as BAM (BaMgAl ₁₀ O ₁₇ )). It is preferable to use what is comprised including. As in this configuration example, when the semiconductor light emitting element is used as an excitation light source of the phosphor 110, high intensity white light can be obtained with high luminous efficiency, and the intensity of white light can be easily adjusted. Changes in temperature and chromaticity can be kept small.

Fourth Embodiment
In the fourth embodiment, instead of the four color LEDs 20a to 20d, illumination of an observation target is performed using a broadband light source such as a xenon lamp and a rotary filter. In addition, instead of the color imaging sensor 38, an imaging target may be imaged by a monochrome imaging sensor. The other respects are the same as in the first embodiment.

  In the endoscope system 200 shown in FIG. 18, in the light source device 14, instead of the LEDs 20 a to 20 d of the endoscope system 10, a wide band light source 202, a rotation filter 204 and a filter switching unit 206 are provided. . Further, in the imaging optical system 30b, instead of the color imaging sensor 38, a monochrome imaging sensor 208 provided with no color filter is provided.

  The broadband light source 202 is a xenon lamp, a white LED, or the like, and emits broadband light ranging in wavelength from blue to red. The rotation filter 204 includes a normal mode filter 210 provided on the closest inner side near the rotation axis, a special mode filter 212 provided on the outer side of the normal mode filter 210, and a further outside of the special mode filter 212. And a filter for mixed mode 214 provided in (see FIG. 19).

  The filter switching unit 206 moves the rotary filter 204 in the radial direction. Specifically, the filter switching unit 206 inserts the normal mode filter 210 into the optical path of the wide band light when the mode switching unit 13c sets the normal mode. When the special mode is set, the filter switching unit 206 inserts the special mode filter 212 into the optical path of the broadband light. The filter switching unit 206 inserts the mixed mode filter 214 into the optical path of the broadband light when the mixed mode is set.

  As shown in FIG. 19, in the normal mode filter 210, a Bb filter 210a, a G filter 210b, and an R filter 210c are provided along the circumferential direction. The Bb filter 210a transmits wide band blue light Bb having a wavelength range of 400 to 500 nm in wide band light. The G filter 210 b transmits green light G of the broadband light. The R filter 210c transmits the red light R of the broadband light. Therefore, in the normal mode, as shown in FIG. 20, the rotary filter 204 is rotated to direct blue light Bb, green light G, and red light R in a wide band as the illumination light for the normal mode to the observation target. It is irradiated sequentially. In the fourth embodiment, the light emission condition for the normal mode corresponds to “sequentially emitting blue light Bb, green light G, and red light R in a wide band”.

  The special mode filter 212 is provided with a Bn filter 212a and a Gn filter 212b along the circumferential direction. The Bn filter 212 a transmits blue narrow band light Bn of 400 to 450 nm out of the wide band light. The Gn filter 212 b transmits 530-570 nm green narrow band light Gn out of the wide band light. Therefore, in the special mode, as the rotary filter 204 rotates, blue narrow band light and green narrow band light are sequentially emitted toward the observation target as the special mode illumination light. In the fourth embodiment, the special mode light emission condition corresponds to “sequentially emitting blue narrow band light and green narrow band light”.

  The mixed mode filter 214 is provided with a Bb filter 214a, a G filter 214b, an R filter 214c, a Bn filter 214d, and a Gn filter 214e along the circumferential direction. The Bb filter 214a, the G filter 214b, the R filter 214c, the Bn filter 214d, and the Gn filter 214e have the same transmittance as the Bb filter 210a, the G filter 210b, the R filter 210c, the Bn filter 212a, and the Gn filter 212b, respectively. Have. Therefore, in the mixed mode, the rotary filter 204 is rotated, and blue light Bb, green light G, and red light R in a wide band are sequentially emitted toward the observation target as illumination light for the normal mode. As illumination light, blue narrow band light Bn and green narrow band light Gn are sequentially emitted toward the observation target.

  In the endoscope system 200, in the normal mode, whenever the observation target is illuminated with wide band blue light Bb, green light G, and red light R, the observation target is imaged by the monochrome imaging sensor 208. As a result, a Bc image signal is obtained at the time of illumination of wide band blue light Bb, a Gc image signal is obtained at the time of illumination of green light G, and an Rc image signal is obtained at the time of illumination of red light R. A normal image is configured by the Bn image signal, the Gc image signal, and the Rc normal image.

  In the special mode, each time the observation target is illuminated with the blue narrow band light Bn and the green narrow band light Gn, the observation target is imaged by the monochrome imaging sensor 208. As a result, a Bn image signal is obtained at the time of illumination of the blue narrowband light Bn, and a Gn image signal is obtained at the time of illumination of the green narrowband light Gn. A special image is configured by the Bn image signal and the Gn image signal.

  In the mixed mode, each time the observation target is illuminated with wide band blue light Bb, green light G, red light R, blue narrow band light Bn, and green narrow band light Gn, the monochromatic image sensor 208 picks up the observation target. Thereby, the Bc image signal, the Gc image signal, the Rc image signal, the Bn image signal, and the Gn image signal are obtained. An image composed of the Bc image signal, the Gc image signal, and the Rc image signal corresponds to a normal image, and an image composed of the Bn image signal and the Gn image signal corresponds to a special image.

Fifth Embodiment
In the first to fourth embodiments, the endoscope 12 provided with the imaging sensor 38 is inserted into the subject for observation, but instead, in the fifth embodiment, the patient takes a mouth The inside of the subject is observed with a capsule endoscope swallowed from the inside.

  The capsule endoscope system at least includes, for example, a capsule endoscope 300 shown in FIG. 21 and a processor (not shown). The capsule endoscope 300 includes a light source 302, a light source control unit 303, an imaging sensor 304, an image signal processing unit 306, and a transmitting and receiving antenna 308. The light source 302 is configured similar to the light source 20 of the endoscope system 10. The light source control unit 303 controls the drive of the light source 302. In the fifth embodiment, since the mixed mode is always set, the light source control unit 303 controls the light source 302 so that the normal mode illumination light and the special mode illumination light are alternately emitted.

  Similar to the imaging sensor 38 of the endoscope system 10, the imaging sensor 304 is configured of a color imaging sensor. The image signal processing unit 305 performs processing similar to that of the CDS / AGC circuit 40 and the A / D conversion circuit 42 on the image signal output from the imaging sensor 304. The image signal that has passed through the image signal processing unit 306 is wirelessly transmitted to a processor device (not shown) of the capsule endoscope system via the transmission / reception antenna 308. The processor device of the capsule endoscope system is configured in the same manner as the processor device 16 of the endoscope system 10, and also functions as an image processing unit 58. The processor device performs the same processing as that of the first embodiment based on the received image signal.

Reference Signs List 10 endoscope system 12 endoscope 12a insertion unit 12b operation unit 12c bending unit 12c distal end 13a angle knob 13b still image acquisition unit 13c mode switching unit 13d zoom operation unit 14 light source device 16 processor device 18 monitor 19 console 20 light source 20a V-LED
20b B-LED
20c G-LED
20d R-LED
22 light source control unit 23 wavelength cut filter 24 light guide 30a illumination optical system 30b imaging optical system 32 illumination lens 34 objective lens 36 zoom lens 38 imaging sensor 40 CDS / AGC circuit 42 A / D conversion circuit 50 image signal acquisition unit 52 DSP
54 noise reduction unit 58 image processing unit 60 display control unit 62 normal image processing unit 64 special image processing unit 66 image correction unit 70 structure extraction unit 72 color and / or brightness acquisition unit 74 color and / or brightness adjustment unit 76 display Pattern setting unit 80 color and / or brightness storage unit 84 composite image generation unit 100 endoscope system 104 blue laser light source 106 blue-violet laser light source 108 light source control unit 110 phosphor 200 endoscope system 202 broadband light source 204 rotation filter 206 Filter switching unit 208 Imaging sensor 210 Normal mode filter 210a Bb filter 210b G filter 210c R filter 212 Special mode filter 212a Bn filter 212b Gn filter 214 Mixed mode filter 214a Bb filter 214b G filter 214c R filter 2 4d Bn filter 214e Gn filter 300 capsule endoscope 302 light 303 light source control unit 304 the image sensor 305 an image signal processing unit 306 an image signal processing unit 308 transmit and receive antenna

Claims (15)

A light source for emitting the first mode illumination light and the second mode illumination light;
When the observation target including the first structure is illuminated with the first mode illumination light, the observation target is obtained by the first mode display image obtained by imaging the observation target and the second mode illumination light. An image acquisition unit configured to acquire a second mode display image obtained by imaging the observation target when illuminated;
An image correction unit that corrects the display image for the first mode or the display image for the second mode to obtain a corrected image, wherein the first display image for the first mode before correction or the second display image for the second mode An image correction unit that corrects the difference between the color and / or the brightness of one structure so as to reduce the difference;
An endoscope system comprising: The image correction unit
A color and / or brightness acquisition unit for acquiring the color and / or brightness of the first structure from the display image for the first mode;
With respect to the difference between the color and / or brightness of the first structure and the color and / or brightness of the first structure acquired by the color and / or brightness acquiring unit in the display image for the second mode before correction The endoscope system according to claim 1, further comprising: a color and / or brightness adjustment unit that performs correction to adjust the color and / or brightness of the second mode display image so that the difference is reduced. The image correction unit
A color and / or brightness storage unit for storing in advance the color and / or brightness of the first structure;
With respect to the difference between the color and / or the brightness of the first structure in the display image for the second mode before correction and the color and / or the brightness of the first structure stored in the color and / or the brightness storage unit The endoscope system according to claim 1, further comprising: a color and / or brightness adjustment unit that performs correction to adjust the color and / or brightness of the second mode display image so that the difference is reduced. The observation target includes a second structure,
The image correction unit
With respect to the difference between the color and / or the brightness of the first structure and the second structure in the display image for the first mode or the display image for the second mode before correction, the difference is reduced. The endoscope system according to any one of claims 1 to 3, wherein the display image for the first mode or the display image for the second mode is corrected. The image correction unit
Extracting the second structure from the second mode display image to generate a second mode display image after extraction of the second structure, or removing the second structure from the second mode display image And a structure extraction unit that generates a first-mode extracted second mode display image from which the first structure has been extracted;
Correction for adjusting the color and / or brightness of the first structure in the second mode display image is performed with reference to the first mode extracted second mode display image, or the second structure extraction The color and / or brightness adjustment unit performing correction for adjusting the color and / or the brightness of the second structure in the second mode display image with reference to the already displayed second mode display image. Endoscope system as described.   The endoscope system according to claim 4 or 5, wherein the first structure is a mucosal structure, and the second structure is a vascular structure. A display unit for displaying an uncorrected image not corrected by the image correction unit among the first mode display image or the second mode display image, and the corrected image;
The endoscope system according to any one of claims 1 to 6, further comprising: a display control unit configured to control the display unit.   The endoscope system according to claim 7, wherein the display control unit controls the display unit so that the uncorrected image and the corrected image are alternately displayed.   The endoscope system according to claim 7, wherein the display control unit includes a display pattern setting unit configured to set a display pattern including a display time of the uncorrected image and the correction image in the display unit. A composite image generation unit configured to generate a composite image obtained by combining the uncorrected image and the corrected image;
The endoscope system according to any one of claims 7 to 9, wherein the display unit displays the uncorrected image, the composite image, and the corrected image.   The first mode illumination light emits light of one or more colors under the first mode emission condition, and the second mode illumination light includes one or more colors of light. The endoscope system according to any one of claims 1 to 10, wherein the light is emitted under a second mode light emission condition different from the mode light emission condition. When the illumination light for the first mode is light which simultaneously emits the light of the plurality of colors, the display image for the first mode images the observation target in which the light of the plurality of colors is simultaneously illuminated. Image obtained by
When the illumination light for the first mode is light which sequentially emits the light of the plurality of colors, the display image for the first mode sequentially images the observation target in which the light of each color is sequentially illuminated. The endoscope system according to claim 11, which is an image obtained by When the illumination light for the second mode is light which emits the light of the plurality of colors simultaneously, the display image for the second mode images the observation target in which the lights of the plurality of colors are simultaneously illuminated. Image obtained by
When the illumination light for the second mode is light that sequentially emits the light of the plurality of colors, the display image for the second mode sequentially images the observation target in which the light of each color is sequentially illuminated. The endoscope system according to claim 11 or 12, which is an image obtained by A light source for emitting the first mode illumination light and the second mode illumination light;
When the observation target including the mucous membrane structure is illuminated with the first mode illumination light, the observation target is illuminated with the first mode display image obtained by imaging the observation target and the second mode illumination light An image acquisition unit for acquiring a second mode display image obtained by imaging the observation target in the case of
An image correction unit that corrects the display image for the first mode or the display image for the second mode to obtain a corrected image, wherein the first display image for the first mode before correction or the second display image for the second mode An image correction unit that corrects the difference between the color and / or the brightness of one structure so as to reduce the difference;
A display control unit that controls the display unit;
The image correction unit
A color and / or brightness acquisition unit for acquiring the color and / or brightness of the mucous membrane structure from the display image for the first mode;
With respect to the difference between the color and / or brightness of the first structure and the color and / or brightness of the first structure acquired by the color and / or brightness acquiring unit in the display image for the second mode before correction And a color and / or brightness adjustment unit that performs correction to adjust the color and / or the brightness of the second mode display image so that the difference is reduced.
The display control unit controls the display unit to alternately display the display image for the first mode and the display image for the second mode after the brightness adjustment by the brightness adjustment unit. system. Emitting a first mode illumination light and a second mode illumination light;
When the image acquisition unit emits the first mode display image obtained by imaging the observation target including the first structure when emitting the first mode illumination light and the second mode illumination light Acquiring a second mode display image obtained by imaging the observation target;
The image correction unit corrects the display image for the first mode or the display image for the second mode to obtain a corrected image, and the display image for the first mode before correction or the second mode Correcting the difference between the color and / or the brightness of the first structure in the display image so as to reduce the difference;
Method of operating an endoscope system comprising: